Left Atrial Abnormality Linked to Vascular Brain Injury

NASHVILLE — Patients with left atrial abnormalities have a higher risk of vascular brain injury even without atrial fibrillation, according to a study presented at the American Stroke Association's International Stroke Conference 2015.

Atrial fibrillation is already known to be a risk factor for vascular brain injury. The researchers wanted to explore this further to see if left atrial abnormalities were associated with vascular brain injury even when atrial fibrillation is not present.

The study included 3,129 participants aged ≥65 years from the Cardiovascular Health Study who had undergone at least one MRI scan. Participants whose ECG showed atrial fibrillation or who had a prior atrial fibrillation diagnosis were excluded. The researchers looked for associations between left atrial abnormality with brain infarcts and leukoaraiosis. They used ECG to examine P-wave terminal force in lead V1 (PTFV1), the most commonly-used ECG measure of left atrial abnormality, as their primary predictor. Follow-up scans were performed five years later, with 1,839 participants completing the follow-up.

The researchers looked separately at participants with at least one scan and participants who had two scans. Among those with at least one scan, each standard deviation increase in PTFV1 was associated with a 0.05-point higher baseline white matter grade (on a 10-point scale). PTFV1 was also associated with prevalent infarcts of any type, particularly non-lacunar infarcts. Among those who had two scans, PTFV1 was linked to worsening leukoaraiosis, but was not associated with incident infarcts.